O'Brien plays Jeff Toland, an attorney who arrives to set up a law practice in a town where the railroad is expected to pass through.
Jeff ends up in the middle of a battle between some poor townspeople and a group of self-styled "vigilantes" who are actually crooks who want to take over the town land themselves and make a fortune when the railroad arrives.
Jeff also finds romance in the person of Ellen Ives (Virginia Vale), whose father started the original vigilante group.
THE MARSHAL OF MESA CITY (1939), LEGION OF THE LAWLESS is still a very good, entertaining "B" Western which I found fun to watch. The plot may sound standard issue, but O'Brien's intelligence and attitude raise the film to a higher level.
It's not simply that O'Brien is playing a lawyer who also happens to be strong and good with a gun, but it's O'Brien's thoughtful approach to the material that makes the difference. He comes across as a smart man who is always strategizing a step ahead. He is slow to anger, tolerantly amused by villains' idiocy for a time, yet ready to be the first to step in and act to correct injustice.
O'Brien also seems to be having a very good time; the laughter he shares with his frequent costar, Virginia Vale, is infectious. The viewer feels that both the character and O'Brien the actor are enjoying life, and that's a very attractive quality.
David Howard. The cinematography was by Harry J. Wild, whose credits included titles such as STATION WEST (1948) and PITFALL (1948).
The supporting cast includes Herbert Haywood, Norman Willis, Hugh Sothern, Mary Field, and Delmar Watson. The film runs 59 minutes.
LEGION OF THE LAWLESS is available in a three-film DVD set from the Warner Archive along with THE MARSHAL OF MESA CITY (1939) and TRIPLE JUSTICE (1940).
The DVD can be rented from ClassicFlix.
LEGION OF THE LAWLESS is also shown from time to time on Turner Classic Movies.